Dishwasher with improved liquid inlet system



Oct. 17, 1967 L. J. MARTINIAK 3,347,250

DISHWASHER WITH IMPROVED' LIQUID INLET SYSTEM 2 Sheets-Sheet 1 Filed June 14, 1965 INVENTQR. Leonard J. Morhmok BYQ W Afnorney Oct. 17, 1967 L. .1 MARTINIAK 3,347,250

DISHWASHER WITH IMPROVED LIQUID INLET SYSTEM Filed June 14 1965 2 SheetsSheet n:

H W 25 i a m INVENTOR. 27 24 23 24 Leonard J. Mornmak WMLW Af'rorney United States Patent Office 3,347,250 Patented Oct. 17, 1967 3,347,250 DISHWASHER WITH IMPROVED LIQUID INLET SYSTEM Leonard J. Martiniak, Waukesha, Wis., assignor to General Electric Company, a corporation of New York Filed June 14, 1965, Ser. No. 463,606 14 Claims. (Cl. 134-182) ABSTRACT OF THE DISCLOSURE A liquid inlet system for an automatic dishwasher including a washing enclosure with a top wall formed in two different levels. An opening is formed in the part of the top wall interconnecting the two levels. A nozzle is spaced from the opening to project liquid therethrough. A baffle is provided within the enclosure to prevent escape of liquid during operation of the dishwasher.

This invention relates to automatic dishwashers, and more particularly to an automatic dishwasher wherein an improved water inlet system is provided.

Dishwashers presently on the market today do not utilize any of the energy of the incoming water during washing operations, that is, neither the pressure of the system supplying the water nor the temperature of the water is utilized during its introduction. Rather, dishwashers operate entirely on the basis of recirculation of the water after it has been introduced.

While it is known to introduce water in a spray into a dishwasher, such dishwashers have not been put into practical use; one important reason for this is that they have invariably failed to meet the very important requirement that a suitable air gap be provided between the water supply system and the confines of the dishwasher tub. This is most significant: in the event that, at the same time, there should be a malfunctioning of the dishwasher, causing the tub to fill, and a breakdown in the water supply system causing a negative pressure therein, a siphoning elfect might be created if the water supply system were in direct contact with the dishwasher tub. If this should occur, vitiated water would then enter the water supply system. For this reason, virtually all plumbing codes require the provision of a suitable air gap which will preclude even the rern-otest possibility of such an occurrence.

And yet, there are advantages to be obtained from having the water enter in a finely divided form. For one thing, the introduction of the water would effect some degree of cleansing of food particles off the dishes. This has high significance where, for instance, as is the case in most built-in domestic automatic dishwashers, an initial purge is provided. The purge is effected by letting water in and then directly back out again so that cooled off water in the line will be purged, and the initial recirculation operation will be with hot water.

In addition to mechanically removing food particles from the dishes, spraying in the water has the desirable effect of raising the temperature of the dishes. Of course, this is not the case with the ordinary approach of letting water flow in down the side.

It is well known in the dishwasher art that a significantly better washing operation is achieved when the temperature of the dishes themselves has been raised, than where the dishes are cold. Quite often, the water which passes through a dishwasher during the initial purge operation may be warm, or even hot. With a spray, this water would be used to elevate the temperature of the dishes. With the present systems, it is not so utilized.

A third, possibly even more significant, factor arises from a phenomenon present in virtually all dishwashers under certain circumstances which is called blowout." When very hot water is suddenly recirculated in finely divided form in large quantities, as may be true during a recirculation operation, in an enclosure filled with relatively cool air, the air expands so suddenly that it carries actual particles of liquid with it as it blows out through the vent of the tub. Such vents are generally at the front of built-in dishwashers. While the temperature of the water, because of its finely divided condition, is not high enough to cause injury by the time it passes through the vent, it can nonetheless be a somewhat upsetting experience to a person standing in front of the dishwasher. In addition, either the floor or the person will become wet, which is, of course, disagreeable in either event.

This undesirable phenomenon is prevented by spraying in the supply of water. The water enters at a much lower rate than it is recirculated, and therefore the cool air in the dishwasher is heated at a relatively slow rate, even where the incoming water is very hot to start with. This slower rate of heating of the air prevents the very rapid expansion of the air and the consequent entrainment of water droplets.

For all of the above reasons, it is highly desirable, and therefore an object of this invention, to provide, for a dishwasher, a spray type inlet which is fully in accord with the existing plumbing codes.

A further more specific object of my invention is to provide such an inlet without utilizing: any excess space, either above or on the side of the dishwasher, since, particularly in built-in dishwashers, space is at very much of a premium.

In oneaspect of my invention 1 provide a dishwasher where the washing enclosure is formed as usual with bottorn, top and side walls, and where at least one of the walls is movable so as to provide access to the enclosure. The top wall is formed in at least two different levels, with the lower of these two levels being adjacent an edge of the top wall, and with an opening being formed in the part of the top wall which joins the two levels. In cooperation with this opening, there is a water inlet nozzle positioned on the lower level and which is adapted to be connected to a source of washing fluid under pressure. This nozzle is in close but spaced horizontal alignment with the opening, and in close but spaced vertical relationship to the bottom edge of the opening.

With this arrangement up at the top of the dishwasher, it then becomes relatively simple to provide whatever baflling is necessary to prevent water from splashing back out through the inlet opening without taking up any useful space within the dishwasher. Also, by virtue of providing one portion of the top wall at a slightly lower level than the rest, it becomes possible to provide the water inlet system without taking up any additional useful room, either at the top or the side of the rectangular space normally provided for such dishwashers.

The subject matter which I regard as my invention is particularly pointed out and distinctly claimed in the concluding portion of this specfication. My invention, however, together with further objects and advantages thereof, may best be understood by reference to the following description taken in conjunction with the accompanying drawings.

In the drawings, FIGURE 1 is a view in perspective, partly broken away to show details, of a dishwasher of the built-in type, that is, of the type which is intended to be secured under a kitchen counter in :a permanent relationship to the counter;

FIGURE 2 is a top plan view, the dishwasher of FIGURE 1;

FIGURE 3 is a view along line 33 of FIGURE 2;

FIGURE 4 is a view along line 44 of FIGURE 3; and

partly broken away, of

FIGURE is a view of the improved inlet assembly of this invention as viewed from line 5-5 in FIGURE 4. Referring now to FIGURE 1, there is shown a dishwashing machine 1; in this case the dishwasher is specifically of the built-in type, although in the broadest aspect of my invention this is not necessarily the case. Dishwasher 1 has an enclosure or tub 2 formed with sides including a back wall 3, side walls 4, and a front wall 7, a bottom section or wall 5, and a top wall 6. The dishwasher illustrated is of the front opening or a drop-door type, that is, front wall 7 is formed as a door pivotable about its base 8 from the vertical position shown to a generally horizontal position (not shown) as is well known in the art. Within the tub 2 there are a pair of vertically spaced racks 9 and 10 adapted to receive dishes for washing. When door 7 is closed the racks are in the position shown, but when the door is open the racks may roll forward in a manner well known in the art to a position wherein they are readily accessible to an operator for loading and unloading operations. Within the dishwasher, there is an an appropriate pumping system, generally shown by the numeral 11, for recirculating water within tub 2 so as to eifect washing of dishes during washing operations, and for removal of water subsequent to each washing or rinsing operation.

It will be understood that the rack structure, the front door structure, and the washing system may be of any type well known in the art. For instance, one such system is shown in my US. Patent No. 3,213,866, for Dishwashing Apparatus With Conical Spray Device Means and assigned to the same assignee as the present application.

The operation of the dishwasher may be initiated by the operator by the use of a manually operable member 12. Then, as is conventonal in the art, an appropriate series of washing, rinsing and drying operations will be provided and thereafter operation will terminate.

The dishwasher is connected to a source of water under pressure (not shown), normally a conventional municipal Water system. A valve (not shown) is controlled in the usual way so as to permit water to come from the water system through a conduit 13 to an inlet system generally indicated at 14 in FIGURES 1 and 2. The valve (not shown) is controlled so as to permit the passage of water through conduit 13 at the beginning of all washing and rinsing operations. In addition, it is conventional in many dishwashers, as has been mentioned above, to provide a purge operation at the very beginning of a dishwashing cycle. In the purge operation, water is allowed to flow for a predetermined length of time sufiicient to permit removal of all the relatively cool water which may be in the pipes, so that when the first recirculation operation starts, it will be effected with water coming right from the hot water heater normally found in residences. During such a purge operation, at the same time that the water is entering, the system 11 is effecting removal of this water, rather than recirculating it, as is the case during washing and rinsing operations.

Referring now to FIGURES 1, 2 and 3, top wall 6 of the dishwasher is formed so as to have an upper level 15 and a lower level 16. Lower level 16, as is particularly well shown in FIGURE 1, is adjacent the edge 17 joining side wall 4 to top wall 6. While the vertical distance between the two levels 15 and 16 is not particularly great (for instance, inch constitutes a desirable structure), it does provide sufiicient room for an opening 17 to be provided in a plane which is at a substantial angle to the horizontal, joining the two levels 15 and 16 of top wall 6.

Secured to the top wall, and preferably to the lower level thereof, is an inlet assembly 18. Assembly 18 includes a tubular inlet section 1? connected to the conduit 13. This may be effected, in the conventional manner, by forcing the end of a conduit over the tubular portion 19 and then clamping it thereon with a suitable clamping member 20. Assembly 18 is secured to lower level 16 by a flange 21, formed as an integral part of the assembly, which extends beneath the main portion of the assembly, passing through the bottom part of opening 17 and then extending back under level 16, where it is fastened to level 16 by any conventional means such as threaded fasteners 22.

The tubular portion 19 of assembly 18 communicates with a nozzle section 23. Nozzle section 23 is formed as a flat, wide orifice; this can best be seen by observing the small vertical height of the orifice, as shown in FIGURE 3, and the substantial width of the orifice, as shown in FIGURES 4 and 5. It will further be observed that the outlet of the nozzle is substantially wider than the inlet, which necessarily is of the same width as the diameter of tubular portion 19. Thus, water passing through orifice 23 is guided in a fiat, wide stream extending out substantially in a horizontal plane.

This jet of water is further guided in its movement in this direction by vertical walls 24 and 25 of the assembly. It will be observed that these vertical walls are separated by a space 26, with the inner walls 25 being joined to the remainder of assembly 18 only by bottom wall 27 extending through the lower portion of opening 17. The general relationship of all these walls is best shown in FIGURE 5, wherein it will further be observed that a top wall 28 joins the side walls 25 to form a complete guiding housing, or enclosure, 29 positioned partly within and partly without opening 17 (FIGURE 3).

The net effect of the assembly 13 is to cause a fan-shaped jet to issue from orifice 23. To the extent that it is needed, further guidance for the fan-shaped jet is provided by walls 24 and housing arrangement 29. The gap between walls 24 and 25 provides the air gap which is so important in apparatus of this type.

To phrase it differently, gap 26 provides, in effect, a functionally effective distance separating the end 30 of nozzle section 23 in a horizontal direction from opening 1'7. Further, a functionally effective vertical distance is provided between the end 30 of the nozzle and the bottom of opening 17. What this does, then, is to insure that if the tub 2 should, through some malfunctioning, fill with water and overflow through opening 17, the water thus issuing from the tub will flow along level 16 and down the sides of the tub and will not be able to flow through the nozzle 23 into the conduit 13 because there is no physical support which will permit the water to get back across gap 26. This means that there is no possibility of vitiated water being drawn back into the water supply system, and that the requirements of the plumbing code are thus met.

The positioning of the nozzle in close but spaced horizontal relationship to opening 17 and the shape of the jet issuing from the nozzle, cause the water to pass in through the opening 17 to the interior of tub 2. As shown in FIG- URES 1 and 2, assembly 18 is positioned in one corner of top wall 6 facing inwardly from that corner, i.e., facing the diagonally removed corner, with the lengthwise dimension of opening 17 being perpendicular to a diagonal line drawn between the two corners. Thus, the fan shaped jet issuing from the nozzle will assume the outline shown by the dotted lines 31 in FIGURE 2.

This fan shaped jet of water passes through a generally horizontally formed space between the top level 15 and a bafiie member 32 which extends in a plane parallel to the plane of the top level and is, in fact, preferably an extension of level 16. As shown, baffle 32 may, in fact, be secured to level 16 by the same threaded members 22 which secure assembly 18 in place. The baflle member 32 is formed with a number of louver sections 33 slanted, as shown, with openings 34 being provided between them. This provides a two-fold effect. First, when water is being recirculated in large quantities within tub 2 by system 11, it acts as a barrier preventing the water from being thrown out of the top of tub 2 through opening 17. Secondly, whenever any part of the fan shaped jet of water issuing from orifice 23 should drop sufiiciently to contact the baffle 32, any water thus remaining on the baffle 32 may flow down through the openings 34 into the lower part of tub 2. The overall shape of member 32 can readily be seen in FIGURE 2, where it is shown as being fan shaped so as to provide a substantiallyenclosed passage between level 15 adjacent opening 17 where the water enters the space above baffle 32, and the inner end of the baflle, removed from opening 17, where the water comes out into the tub proper.

A further structural feature to be noted is the series of arcuate corrugations, generally shown at 35, which are formed in the top 6 of the tub. corrugations 35 are partly beyond the outer end of baffle 32 and partly above the outer end of the bafile. The corrugations have the purpose of preventing the water being recirculated at high velocity, and in large quantities, within tub 2 during a washing operation from splashing out through opening 17. With the corrugations, the inner surface of top 6 is formed as a number of short surfaces slanted at such an angle that water striking them from below will be directed back down rather than there being any possibility that it will be directed out through the opening 17.

In summary, then, it will be observed that the water inlet for tub 2 is through assembly 18, and more specifically through the nozzle portion 23 thereof, across the gap 26, through opening 17, then in a flat shaped jet through the space between baffle 32 and top 6 of the tub, and then into the tub itself. During the entry of water in this manner an efiective washing down of the dishes within the dishwasher is provided. This is highly desirable since many dishwashers, as described, include a purge operation wherein the water passed through the dishwasher normally goes to waste.

Further, the possibility of blowout is eliminated because the water is being brought in at a slow enough rate so that, even though it may be very hot water, therate at which the air within the dishwasher is heated is not rapid enough to cause the undesirable phenomenon described. In addition, the air gap required by most plumbing codes, and which prevents any possible siphoning of vitiated water back into the water supply system, is effectively provided, with no extra room being taken up, and with no useful room being removed from the interior of tub 2.

The structure is thus economical compared to previous water inlet systems, compact with respect to the amount of addition-a1 room taken up outside the confines of the tub when comared with such previous systems, and performs highly useful functions upon entering the tub, which has not been true of any previously used system which met the prevail-ing plumbing requirements.

While in accordance with the patent statutes I have described what at present is considered to be the preferred embodiment of my invention, it will be obvious to those skilled in the art that various changes and modifications may be made therein without departing from the invention. I aim, therefore, in the appended claims, to cover all such changes and modifications as fall within the true spirit and scope of my invention.

What I claim as new and desire to secure by Letters Patent of the United States is:

1. A dishwasher comprising:

(a) a washing enclosure formed with a bottom wall, a top wall, and side walls, at least one of said walls being movable to provide access to said enclosure;

(b) said top wall being formed in at least two different levels, with the lower of said levels being adjacent an edge of said top wall, said top wall having an opening formed between said levels;

(0) and a water inlet nozzle positioned outside said washing enclosure on the lower level and adapted to be connected to a source of washing fluid under pressure, said nozzle being in close but spaced horizontal alignment with said opening and in close but spaced vertical elevated relationship to the bottom edge of said opening.

2. The apparatus defined in claim 1 wherein one of said side walls is pivotally mounted for movement about its bottom to provide access to said enclosure.

3. The apparatus defined in claim 1 wherein said opening is substantially in the form of a horizontally extending slot, and said nozzle is formed to eject in a horizontal direction a substantially fan shaped jet of water through said slot.

4. The apparatus defined in claim 1 wherein said opening is formed adjacent a corner of said top wall and a fan shaped horizontally extending battle is secured within said enclosure just below said opening.

5. A dishwasher comprising:

(a) a washing enclosure formed with a bottom wall,

a top wall, and side walls, at least one of said walls being movable to provide access to said enclosure;

(b) said top wall having an opening formed in a plane at an angle to the horizontal adjacent an edge thereof;

(c) and a water inlet nozzle outside said washing enclosure adapted to be connected to a source of washing fluid under pressure, said nozzle being in close but spaced horizontal alignment with said opening, and in close but spaced elevated vertical relationship to the bottom edge of said opening.

6. A dishwasher comprising:

(a) a washing enclosure formed with a bottom wall, a top wall, and side walls, at least one of said walls being movable to provide access to said enclosure;

(b) said top wall being formed in at. least two dilferent levels with the lower of said levels being adjacent an edge of said top wall, said top wall having an opening formed betweensaid levels;

(c) a bafile secured within said enclosure in closely spaced relation to said top wall and extending horizontally from said opening thereby to provide'a horizontally extending inlet passage from said opening into said enclosure;

(d) and a water inlet nozzle positioned outside said washing enclosure on the lower level and adapted to be connected to a source of washing fluid under pressure, said nozzle being in close but spaced horizontal alignment with said opening and in close but spaced elevated vertical relationship to the bottom edge of said opening.

7. The apparatus defined in claim 6 wherein said bafile is formed with a plurality of louvers with open spaces be tween them, said louvers being tilted at an angle so as to slant downwardly facing toward said opening.

8. A dishwasher comprising:

(a) a washing enclosure formed with a bottom wall,

a top wall, and side walls, said side walls providing a substantially rectangular cross-section for said enclosure, at least one of said wall-s being movable to provide access to said enclosure;

(b) said top wall being formed in at least two different levels with the lower of said levels being adjacent one corner of said top wall, said top wall having a slot-like opening formed between said levels extending in a direction substantially perpendicular to a diagonal line drawn between said one corner and the opposite corner of said enclosure;

(c) and a water inlet nozzle positioned outside said washing enclosure on the lower level and adapted to be connected to a source of washing fluid under pressure, said nozzle being in close but spaced horizontal alignment with said opening and in close but spaced elevated vertical relationship to the bottom edge of said opening.

'9. A dishwasher comprising:

(a) a washing enclosure formed with a bottom wall, a top wall, and side walls, at least one of said walls being movable to provide access to said enclosure;

(b) said top wall being formed in at least two different levels, with the lower of said levels being adjacent an edge of said top wall, said top wall having an opening formed between said levels, said top wall upper level having a portion adjacent said opening shaped to inhibit the splashing of water from said enclosure back out through said opening;

(c) and a water inlet nozzle positioned outside said washing enclosure on the lower level and adapted to be connected to a source of washing fluid under pressure, said nozzle being in close but spaced horizontal alignment with said opening and in close but spaced elevated vertical relationship to the bottom edge of said opening.

10. The apparatus defined in claim 9 wherein said portion of said upper level of said top wall is corrugated, thereby to provide a series of short, slanted surfaces adjacent said opening.

11. For use in a dishwasher having a top wall formed with an opening in a plane at an angle to the horizontal, an inlet assembly adapted to be connected to a source of washing fluid under pressure so as to introduce such fluid into the dishwasher through the opening across an air gap, wherein said inlet assembly comprises a nozzle positioned outside said dishwasher and formed to eject a horizontal substantially fan shaped jet of water, a housing aligned with said nozzle to guide said fan shaped jet of water, said housing having top and bottom surfaces and side surfaces converging from their ends removed from said nozzle to their ends near said nozzle, said housing and said nozzle being separated by an air gap across which such jet of water must pass without physical support, said housing and said nozzle being joined to each other solely by the bottom portion of said housing.

12. A dishwasher comprising:

(a) a washing enclosure formed with a bottom wall,

a top wall, and side walls, at least one of said walls being movable to provide access to said enclosure;

(b) said top wall being formed in at least two different levels, the lower of said levels being adjacent an edge of said top wall, said top wall having an opening formed between said levels;

(c) and a water inlet assembly secured to the lower level and adapted to be connected to a source of washing fluid under pressure, said assembly comprising a nozzle positioned outside said washing enclosure in close but spaced horizontal alignment with said opening, and in close but spaced elevated vertical relationship to the bottom edge of said opening, said assembly further including a housing guide section positioned partly within said enclosure and joined to said nozzle solely by a floor section extending through said opening below said nozzle.

13. The apparatus defined in claim 12 wherein said nozzle is formed to provide a fan shaped jet of water and said housing is formed with side walls which diverge away from said nozzle from their nearest edges to their farther edges.

14. The apparatus defined in claim 12 wherein said inlet assembly includes a flange member extending from said floor section downwardly and backwardly into engagement with a wall of said enclosure below said assembly, said assembly being secured to said enclosure by said flange member.

References Cited UNITED STATES PATENTS 1,690,974 11/1928 Hazard et a1 134-176 1,728,153 9/1929 Donnellon 134-93 2,417,908 3/1947 Bowen 137-216 X 2,498,179 2/1950 Oliver et a1. 68-207 2,552,852 5/1951 Idle 134-93 2,619,977 12/1952 Hagen 134-182 X 2,704,083 3/1955 Low 134-183 2,764,169 9/1956 Bazarnic 134-110 2,871,871 2/1959 Conlee 68-207 X 2,966,052 12/1960 Syles 68-207 X 3,020,741 2/1962 Waldrop 134-154 X FOREIGN PATENTS 144,315 11/1951 Australia.

CHARLES A. WILLMUTH, Primary Examiner.

R. L. BLEUTGE, Assistant Examiner. 

1. A DISHWASHER COMPRISING: (A) A WASHING ENCLOSURE FORMED WITH A BOTTOM WALL, A TOP WALL, AND SIDE WALLS, AT LEAST ONE OF SAID WALLS BEING MOVABLE TO PROVIDE ACCESS TO SAID ENCLOSURE; (B) SAID TOP WALL BEING FORMED IN AT LEAST TWO DIFFERENT LEVELS, WITH THE LOWER OF SAID LEVELS BEING ADJACENT AN EDGE OF SAID TOP WALL, SAID TOP WALL HAVING AN OPENING FORMED BETWEEN SAID LEVELS; (C) AND A WATER INLET NOZZLE POSITIONED OUTSIDE SAID WASHING ENCLOSURE ON THE LOWER LEVEL AND ADAPTED TO BE CONNECTED TO A SOURCE OF WASHING FLUID UNDER PRESSURE, SAID NOZZLE BEING IN CLOSE BUT SPACED HORIZONTAL ALIGNMENT WITH SAID OPENING AND IN CLOSE BUT SPACED VERTICAL ELEVATED RELATIONSHIP TO THE BOTTOM EDGE OF SAID OPENING. 